To evaluate antimicrobial activities of chongkukjang slime fermented by different strains, growth characteristics were compared using various standard microorganisms with addition of chongkukjang slime. Chongkukgang slime was prepared by fermenting cooked soybean after inoculating with Bacillus circulars K-1, Bacillus spp N-1 and Bacillus subtilis CH-1, respectively. Significant antimicrobial activity was observed by chongkukjang slime on gram positive bacteria (Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Micrococcus luteus), gram negative bacteria(Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas fluorescens), and yeast (Pichia membranaefaciens, Saccharomyces cerevisiae, Candida albicans). In case of B. cereus growth inhibition of 80% was achieved by the addition of chongkukjang slime; on the contrary, to Escherichia coli O157:H7 only 20% inhibition was observed. Slime from Bacillus subtilis CH-1, in parkicular, inhibition of 40% toward bacteria and yeast, whereas slime from Bacillus circulars K-1, Bacillus spp N-1 showed only 20% inhibition.